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17#include <linux/kernel.h>
18#include <linux/ioport.h>
19#include <linux/module.h>
20#include <linux/moduleparam.h>
21#include <linux/delay.h>
22#include <linux/jiffies.h>
23#include <linux/init.h>
24#include <linux/interrupt.h>
25#include <linux/wait.h>
26#include <linux/isa.h>
27#include <linux/i2c.h>
28#include <linux/i2c-algo-pca.h>
29#include <linux/io.h>
30
31#include <asm/irq.h>
32
33#define DRIVER "i2c-pca-isa"
34#define IO_SIZE 4
35
36static unsigned long base;
37static int irq = -1;
38
39
40
41static int clock = 59000;
42
43static struct i2c_adapter pca_isa_ops;
44static wait_queue_head_t pca_wait;
45
46static void pca_isa_writebyte(void *pd, int reg, int val)
47{
48#ifdef DEBUG_IO
49 static char *names[] = { "T/O", "DAT", "ADR", "CON" };
50 printk(KERN_DEBUG "*** write %s at %#lx <= %#04x\n", names[reg],
51 base+reg, val);
52#endif
53 outb(val, base+reg);
54}
55
56static int pca_isa_readbyte(void *pd, int reg)
57{
58 int res = inb(base+reg);
59#ifdef DEBUG_IO
60 {
61 static char *names[] = { "STA", "DAT", "ADR", "CON" };
62 printk(KERN_DEBUG "*** read %s => %#04x\n", names[reg], res);
63 }
64#endif
65 return res;
66}
67
68static int pca_isa_waitforcompletion(void *pd)
69{
70 unsigned long timeout;
71 long ret;
72
73 if (irq > -1) {
74 ret = wait_event_timeout(pca_wait,
75 pca_isa_readbyte(pd, I2C_PCA_CON)
76 & I2C_PCA_CON_SI, pca_isa_ops.timeout);
77 } else {
78
79 timeout = jiffies + pca_isa_ops.timeout;
80 do {
81 ret = time_before(jiffies, timeout);
82 if (pca_isa_readbyte(pd, I2C_PCA_CON)
83 & I2C_PCA_CON_SI)
84 break;
85 udelay(100);
86 } while (ret);
87 }
88
89 return ret > 0;
90}
91
92static void pca_isa_resetchip(void *pd)
93{
94
95 printk(KERN_WARNING DRIVER ": Haven't figured out how to do a reset yet\n");
96}
97
98static irqreturn_t pca_handler(int this_irq, void *dev_id) {
99 wake_up(&pca_wait);
100 return IRQ_HANDLED;
101}
102
103static struct i2c_algo_pca_data pca_isa_data = {
104
105 .write_byte = pca_isa_writebyte,
106 .read_byte = pca_isa_readbyte,
107 .wait_for_completion = pca_isa_waitforcompletion,
108 .reset_chip = pca_isa_resetchip,
109};
110
111static struct i2c_adapter pca_isa_ops = {
112 .owner = THIS_MODULE,
113 .algo_data = &pca_isa_data,
114 .name = "PCA9564/PCA9665 ISA Adapter",
115 .timeout = HZ,
116};
117
118static int pca_isa_match(struct device *dev, unsigned int id)
119{
120 int match = base != 0;
121
122 if (match) {
123 if (irq <= -1)
124 dev_warn(dev, "Using polling mode (specify irq)\n");
125 } else
126 dev_err(dev, "Please specify I/O base\n");
127
128 return match;
129}
130
131static int pca_isa_probe(struct device *dev, unsigned int id)
132{
133 init_waitqueue_head(&pca_wait);
134
135 dev_info(dev, "i/o base %#08lx. irq %d\n", base, irq);
136
137#ifdef CONFIG_PPC
138 if (check_legacy_ioport(base)) {
139 dev_err(dev, "I/O address %#08lx is not available\n", base);
140 goto out;
141 }
142#endif
143
144 if (!request_region(base, IO_SIZE, "i2c-pca-isa")) {
145 dev_err(dev, "I/O address %#08lx is in use\n", base);
146 goto out;
147 }
148
149 if (irq > -1) {
150 if (request_irq(irq, pca_handler, 0, "i2c-pca-isa", &pca_isa_ops) < 0) {
151 dev_err(dev, "Request irq%d failed\n", irq);
152 goto out_region;
153 }
154 }
155
156 pca_isa_data.i2c_clock = clock;
157 if (i2c_pca_add_bus(&pca_isa_ops) < 0) {
158 dev_err(dev, "Failed to add i2c bus\n");
159 goto out_irq;
160 }
161
162 return 0;
163
164 out_irq:
165 if (irq > -1)
166 free_irq(irq, &pca_isa_ops);
167 out_region:
168 release_region(base, IO_SIZE);
169 out:
170 return -ENODEV;
171}
172
173static int pca_isa_remove(struct device *dev, unsigned int id)
174{
175 i2c_del_adapter(&pca_isa_ops);
176
177 if (irq > -1) {
178 disable_irq(irq);
179 free_irq(irq, &pca_isa_ops);
180 }
181 release_region(base, IO_SIZE);
182
183 return 0;
184}
185
186static struct isa_driver pca_isa_driver = {
187 .match = pca_isa_match,
188 .probe = pca_isa_probe,
189 .remove = pca_isa_remove,
190 .driver = {
191 .owner = THIS_MODULE,
192 .name = DRIVER,
193 }
194};
195
196static int __init pca_isa_init(void)
197{
198 return isa_register_driver(&pca_isa_driver, 1);
199}
200
201static void __exit pca_isa_exit(void)
202{
203 isa_unregister_driver(&pca_isa_driver);
204}
205
206MODULE_AUTHOR("Ian Campbell <icampbell@arcom.com>");
207MODULE_DESCRIPTION("ISA base PCA9564/PCA9665 driver");
208MODULE_LICENSE("GPL");
209
210module_param(base, ulong, 0);
211MODULE_PARM_DESC(base, "I/O base address");
212
213module_param(irq, int, 0);
214MODULE_PARM_DESC(irq, "IRQ");
215module_param(clock, int, 0);
216MODULE_PARM_DESC(clock, "Clock rate in hertz.\n\t\t"
217 "For PCA9564: 330000,288000,217000,146000,"
218 "88000,59000,44000,36000\n"
219 "\t\tFor PCA9665:\tStandard: 60300 - 100099\n"
220 "\t\t\t\tFast: 100100 - 400099\n"
221 "\t\t\t\tFast+: 400100 - 10000099\n"
222 "\t\t\t\tTurbo: Up to 1265800");
223
224module_init(pca_isa_init);
225module_exit(pca_isa_exit);
226
